Suborder:
|
Goniatitina
|
Superfamily:
|
Schistoceratoidea
|
Family:
|
Christioceratidae
|
Genus:
|
Christioceras
|
Species:
|
trifurcatum+ |
Qualifier:
|
ss |
Author:
|
Nassichuk & Furnish 1965,p.724
|
Lower Boundary:
|
Langsettian--Duckmantian, Westphal.A--B, 311.3 million years
|
Upper Boundary:
|
U Atokan--Desmoinesian [ATO--DES], 308.6 million years
|